Across
- 4. contains different numbers of electrons
- 6. the positive particle in an atom
- 8. atoms of the same element with a different number of neutrons
- 9. number of protons plus number of neutrons
- 11. smallest particle that makes up protons and electrons
- 13. atoms with either a positive or negative charge
- 14. the center of an atom
Down
- 1. the negative particle in an atom
- 2. different structural forms of the same element
- 3. cloud, part of the atom where the electrons are located
- 5. a verticle row on the periodic table
- 7. a horizontal row on the periodic table
- 10. the particle with zero charge in an atom
- 12. indicates the number of protons in an atom